Male Infertility Is More Complex Than Originally Thought

Scientists search for the answer to male infertility

Millions of men are affected with male infertility each year. The main issue is the inability to produce productive sperm. With yeast as an aid, researchers have begun to identify signals at the molecular to try to determine the causes of this problem.

Researchers have used yeast to learn about epigenetic processes, or, processes that affect gene expression. Using these processes, they found various areas on proteins that may be vital regulators of egg and sperm formation.

Containing only one chromosome of each type, sperm and eggs each have 23 chromosomes. Meiosis, or the formation of gametes by cell divisions, is strictly regulated using molecular processes inside each cell. What experts seek to learn is, which epigenetic players influence this process?

Working to answer that question, scientists created a system to mutate parts of two proteins, histone H3 and histone H4, searching for any defects within the spore formation.

Researchers used more than 100 different mutants to identify any changes to the histone that may influence gamete formation.

The team noticed multiple areas critical to the successful completion of meiosis where changes occurred.

Discovering these changes allowed a method of screen to occur that helped determine epigenetic alterations during the sperm or egg formation process. Also, researchers note how similar the formation of sperm is to that of yeast spores.

Researchers firmly believe some male fertility problems are related to epigenetics.